The invention relates to a motor vehicle seat which can pivot with respect to its underframe in a predetermined direction about a rear axis extending in the transverse direction of the vehicle. The seat is supported on the underframe by means of a front deformation element arranged at a distance from the rear axis, the deformation element only permitting pivoting when a given load is exerted as the result of an accident.
Such a motor vehicle seat is known from German Published Unexamined Pat. Application (DOS) 1,963,335, in which the deformation element is designed as a stretched member wound on a block, the windings of which member are pulled apart with energy absorption when the seat pivots back as the result of an accident.
An object of the invention is to create a deformation element which can easily be adapted to different requirements, is simple to fit and at the same time inexpensive and capable of reducing the affect of the forces introduced from the rear into the backrest by a passenger colliding into it by a deliberate tilting movement of the seat with energy absorption, lessening injury.
This object is achieved by designing the deformation element as an energy absorbing foamed material block surrounded by a shell fastened by fastening devices to the underframe and the underside of the seat, which shell is constructed with predetermined weakened bending points or areas which form folding lines during pivoting of the seat caused by an accident.
Cost advantages are obtained and difficult cross-sectional shapes optimally utilizing the existing space are achieved in certain preferred embodiment wherein the shell consists of an extruded section.
The lateral displacement capability required in particular on an omnibus seat on the central aisle side can be achieved in a simple way in especially preferred embodiments by providing transverse guide tracks molded onto the extruded section at the ends so as protrude on the upper side and lower side to be held adjustable with sliding movement by assigned receptacles of the underframe. It is advantageous in this case if the upper transverse guide track and its receptacle on the underframe side also form the pivoting device for the seat.
An ingress of moisture can be prevented if the shell is completed to form a fully enclosed container by easily deformable, preferably clipped-on wall parts at the ends, in accordance with especially preferred embodiments.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawing.